US2251176A

US2251176A - Terminal and method of making it

Info

Publication number: US2251176A
Application number: US241815A
Authority: US
Inventors: Jr Robert Temple
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-11-22
Filing date: 1938-11-22
Publication date: 1941-07-29
Anticipated expiration: 1958-07-29

Description

July 29, 1941. R. TEMPLE, JR 2,251,176

TERMINAL AND METHOD MAKING 1T Filed Nov. 22, 1938 EV, ne.

l ze

,/26 WOR.

, ATTORNEYS."

Patented July 29. 1,941

\ UNITED STATES PATENT OFFICE 2,251,116 mamar. smrrnon on MAKING rr Robert rompio, n., Pittsburgh, ro. Application November z2, 193s. serial No. 241,815

(ci. 15a-z) 7 end of an electric conductor and simultaneously I 13 Claims;

'I'his invention relates to a terminal or-con' nector for an electric conductor or a strand element, and .to methods for making the same.

, Heretofore, it has been the practice in many electrical installations -to provide electric wires,

cables. or other conductors with terminal tips an electric conductor or other strand element. Y

' which terminal is formed from a short length of togrony with o shank portion adapted to b'e rolded or bent around the endof an electric conductor, or having a socket portion in which the end of the conductor is received. The electric conductor is usually connected to the terminal just described by a soldering or like operation.

Terminals or connectors of the type Just described have been open to the objection that in the larger sizes it is a time-cons' g a'nd la.- borious operation to secure the end of an electric conductor to the terminal, and this is particularly true when working' with metals which are dilcult to solder. Even when apparently soltiered satisfactorily the electrical eillciency of the joint may be low and skilled operators are usually a requisite. Moreover, in thecase of heavy electrical overloads due to shorting or as occasioned by lightning striking the conductors,'the connecting solder has vbeen melted and the terminal released from the conductor. Again, in vmany instances lthe terminals, particularly in the larger sizes, are relatively expensive to make and often require special forming-dies,

tubingthat receives the end o! the conductor, the -tubing being ilattened at one end as is the conductor received therein. the flattened portion having a hole punched therethrough and having the sleeve and electric conductor pressed intimately together ior substantially perfect electric contact.

' Other obiectsof my invention include the protvision of a terminal having means for sealing around the insulation of an insulated wire. and

, the provision of a terminal for connecting dierent metals. such as copper and aluminum The foregoing and other objects oi' my invention are achieved by the provision of a terminal.

i and methods and apparatus for making it, all as 39 is a transverse vertical cross-sectional view .on

It is not uncommon' to require a. considerable varlation in terminal size in a given electrical installation 4so that a large number of dinerentsized terminals must be carried in stock.

the same-scale as Fig.' 3 of the terminal, this viewbeing taken on linefIV-IV of Fig..1; F18. 5 is a iront elevation, partly in section, ci my improved apparatus for forming the terminal oi' Figs. 1 tc 4; Fig.' 6 is a plan view of one of the dies shown in Fig. 5 and-the holding means associated therewith, all as taken substantially on line V'I--VI o! Fig. 5: F18. 7 is a side elevation o! the apparatus shown in Fig. J5, but includes a slightly It is the general object of my invention 640 mOdied '601181302121011 0f the Upper di: and F18 diiiiculties attending` the provision and use of electric terminals or connectors by providing a relatively inexpensive, 'easily applied terminal, and in which the electric conductivity is substanavoid and overcome the foregoing and other tially perfect, and will be maintained so despite A heavy overloads.,

oi improved methods for forming a' terminalon the ends of anelectric wire, cable or other con- V Another object of 'my invention the provision -f 8 is a longitudinal sectional view of a terminal formed from a bimetallic tube. I

In particularly describing my improved terminal or'connector and -methods and apparatus i'or making it as illustrated, for. example. in the drawing, itf should be understood that I contemplate forming a terminal on an electric conductor of substantially any type, as, for example,V la. solid wire, a wire cable, a bus-bar, or the like.

Thus, in the specification andclaims when refductor, and, more broadly, a connector o r tip 'for erence is made to -a wire or electric conductor, it is intended to cover any electric conductor, as, for example. of the several types specically identitled -just above. Also, it might be well to note compressing a short length of tubingaround the. here" that I' contemplate forming a terminal on wires of any of a variety of compositions whichl nect the end of a wire or cable to a given object,`

or to each other, and wherein the wire is not employed in an electric circuit but is used to make a mechanical or load-carrying connection. A`ccordingly, the words terminal,"` "connector, and wire are intended to be broad enough when read in either the specification or claims' to cover a purely mechanical or load-bearing connection instead of, or interchangeably with, an electric circuit connection.

Having particular reference to the accompanying drawing, 'the numeral I0 indicates as a whole an electric conductor, wire, or other strand element which has been illustrated as being formed of a plurality of strands, and including, if desired, a covering I2 of insulation. The bared end of the wire I is received in a short length of metal tubing I4 which has an internal Ybore of such a diameter-as to closely receive and surround the end of the wire. The tubing I4 is preferably formed with a belled or expanded end I5 of a relatively short axial length which is adapted to receive and surroundl the insulation I2 on the wire I0. 'I'he belled end I5 of the tubing I4 effects a seal around the end of the insulation and prevents the entrance of moisture between the end of the insulationand the wire.

vAs particularly shown in Fig. 3, the ends of the wire extendfsubstantially to the outermost end of the tubing I4 and are in fact illustrated flush therewith. The outermost half, ora somewhat greater or less length of the tubing I4, is attened as at I6 and Il by powerful squeezing means as hereinafter described. 'I'he flattening of the tubing serves alsoto flatten the end of `the Wire II), as particularly shown inFigs. 3 and 4, so that the tubing and wire is compressed together in an integral or intimate manner, whichV provides an excellent and substantially perfect electrical contact between the tubing I4 and the wire Ill. I

V.lis-will be evident from Figs. 2 and 3, the flattening ofthe end of the tubing I4 is preferably such that the bottom or lowermost part I1 of the flattened end portion is substantially in alignment-with the bottom of the unattened end f the tubing, whereas the top I3 of the flattened end is considerably onset from the unflattened top of the tubing. As hereinafter described, my

nected into anelectric circuit by a bolt or screw, as will be understood.

Having particular reference to Figs. 5, 6 and 7,

a typical apparatus for forming my improved connector or terminal comprises a frame indi-,

be formed integrally with the piston in the manner shown in Fig. 5.

Cooperating with the die 4member 3B is a female die 32 which is supported on the anvil 26. Like the die member 30 the die 32 can be made integral with the anvil 26 or can be received in a suitable recess in the anvil, as shown,

so that ldies of different sizes can be interchanged' on the anvil. The die 3'2 is 'provided with a channel 38 adapted to receive the end of the tubing I4, as shown in dotted lines. which tubing has the wire, end extending therein. I preferably position the tubing I4 and the wire Ill with relation to the die 32 and in the channel 38,` and preferably accomplish this by forming the die 32 with a closed end 34 against which the end of the tubing I4 andthe end of the wire I0 can abut, although this is not requisite to successful operation. Suitable means, such as a pair of spring fingers 36, secured to the anvil 26, are generally incorporated vwiththe apparatus for centering the tubing I4'laterally of the die 32.

' It will be recognized that the tubing can be improved methods and vapparatus effect this type' of ilattening of the tubing and wire which is desirable for the rason that the terminal can arm, nat, eiecare inclined slightly outwardly. This shape permits the removal of the terminal end vfrom the forming dies as hereinafter described, The flattened end of the tubing or terminal asflust described is formed with an aperture, usually round; therethrough which has been identind by the numeral Il. This aperture serves to persprung down betweenfthe fingers 36 and will be positioned thereby centrally of the channel 33 during the flattening of the tubing end, and that the flattened tubing can be quickly released from between the spring lingers after the terminal-forming operation.A

The channel or channel-shaped -opening 3B provided in the die 32, which channel receives the end of the tubing, is formed with side walls which are inclined slightly outwardly so that the flattened end of the terminal. can readily be re moved from the die.' Itwill be understood that the lateral distance between the sides of the channelrdetermines the width of the flattened terminal end. The die member 31|, as heretofore stated, is complementary to the channel 3l in theVv `in*1"ig. '1, and provide the d ie 32 and the anvil 23 with aligned apertures 42 which receive the.

slug punched out lof the flattened end. Preferably. I provide the piston 23 with a reciprocable Weight u which is slldably clrletkln 8. longltudinal bore 431m the piston'add secure apunch rod 4C to the weight `44. The end of the punch -'rod 4l in the normal uppermost position of the weight 44 is such that the end of the punch .rod

46 is flush with the bottom of the die member mit the flattened end of the terminal to be con- 7'5 3l, as lshown. The weight 44 is normally held at the uppermost end of the bore 45 by a light weight compression spring 48.

I commente increasing the length fI the die `a2 .so .that the lower side of the,l tubing I4 is sup- Thex construction and arrangement .of the 5 weight 44 and punch rod 46 and associated spring 48 is such that when the piston 28 vis driven downwardly to bring the die member'30 into engagement with the die 32, the end of the punch rod 46 ush with the end o! the die member 80 acts to rst compress and flatten the end of the tubing. received between the' dies. When the attening movement of the dies together is stopped by the complete .compression-of the flattening portion, then the momentum of th weight 44'is such that it drives forward to force 4the punch rod 46 through the 'flattened end of the terminal to thereby punch a slug out of the aperture 42 in the die 32 and the anvil 26. This punching action commences' oniy near the end of theattening operation on the tube and, because of this, has been'found to provide a some- Aported over substantially ,its-full length, which prevents any oisetting in this side or bottom of,

the tubing. f

If the die member 30 is formed with the integral punch 40 as shown in Fig 'Lm aperture,... n 0r hole is punched through the flattened end of thev tubing andthrough the'wire in the flattened end, and this punching operation is done subv stantially simultaneously with the flattening of the tubing. On the other hand, in the form of my invention shown in Fig. 5, once the end of -the tubing has been attened and the downward -movement of the piston 28 substantially arrested,

the weight '44 continues to move forward under its own momentum to thereby drive the punch rod 46 through the flattened terminal end'to 'provide a round hole therethrough. After the what cleaner-cut flattening and punching of the terminal end.

The operation oi the punching mechanism as l:lust described is dependent upon building up a comparatively high momentum in the piston 28 during the flattening stroke of the dies together,-

and, as hereinafter described, is largely dependeptupon driving the piston 28 by the detonation of an explosive charge. I contemplate shortening the length of the punch rod 48 so that the lowermost end of the punch rod is some distance from the bottom end of the die 36. This conattening .and punching operation has been achieved as .just described, the piston 28 is pushed back up into the barrel .24 and the terminal and wire are readily removed from between the spring -ngers 36 and the die 32 and a newv tubing with a wire therein is inserted into the channel 38 of the die 32, and the operation is repeated. m

In the form of terminal vshown in Fig. 8, the

tubing employed is a bimetallic tubing adaptedI to be used to connect two different metals. Specically, the numeral 60 indicates an aluminum struction increases the momentum and punching action ofA the weightf44 and punch rod 48 in the downward stroke of the piston 28 so that the punching action-follows the 'complete nattening of the end o! the tubing by the die member 80.

In order to drive the piston 28.with high velocwire to which the 'compoundtube 62-64 is secured.'l 'I'he inner tubing 62 is aluminum where.

`as the outer tubing 64 is copper, although it ity the end of the barrel 24 of the apparatusremote from the anvil 28 is formed with a breech' and a removable breech-block and iiring-pinl of' the' type, for example, shown in'my Patent No. 2,030,803, so that this portion or the apparatus, indicated as a whole by the numeral 60,will not be described infdetail. Sulce it to say that the breech-block is removable so that the breech end of the barrel can recelvea blank cartridge which can be detonated through a iiring-pin4 associated with the breech-block when the breech-block is replaced over the end of the barrel.

In the operation of the apparatus shown in Figs. 5 to 7, the bared end of-a wire III is inserted into a "short length of tubing I4, and the end of the tubing and wire is abutted against the end 34 of the die 82 with the tubing and wire end being received in the channel 38 of the die. The tubing and wire end is held in properly centered relation -in the channel by the spring iln'ge'rs 36. The piston 28 is then pushed Aback up to the breechend of the barrel 24, the breechblock onthe end of the barrel-is removed and a blank cartridge. or other suitable explosive means is inserted in the breech, and the breechshould be expressly understood that other metals can be used ,to make any particular conditions.

For instance, in the example' given an a uminum wire is adapted to be connected to a co per busbar by the bimetallicV terminal, having the inner ntubing of aluminum engaging ywith the aluminum wire and the outer tubing of copper engaging with the copper bus-bar. The very high pressure used to press'. the term/Inal'causes such intimate contact between the different metal parts of the bimetallic tube that there is little or no electrolysis or corrosion between these parts. So far as I am aware, electrical connections betwei diillerent metalsr such as copper and aluminum, have always resulted in very undesirable electrolysis\ and corrosion. By selecting a bimetallic tube having an inner tubing of the same metal as the wire and an outer tubing of the same metal as the other member to be connected, I am able to substantially eliminate corrosion as stated above.

block is then replaced. Now the ring-pin .is

operated to'detonate the explosive charge which drives the piston down through the barrel 24 of the apparatus with great speed and power and causes the die'member' 80 to engage with the side of the outermost end of the tubing to attenkthe tubing and wire therein against .the'bot- 'tom of the channel 38 in the die 82. Striking the high velocity blow such as :lust described causes the flattening to occur; substantially all,

on the uppervside .of the terminal, as will be evi-A dent from thel terminal shown in Figs. -1 4.

The terminal of Fig. 8 has beenillustrated as having an equal oil'set on both its top and bottom. This is eilected by shortening the die 32 so that the bimetallic tube '62-64 is supported by the die only along the bottom of that portion of the tube which is vilattened as distinguished from the longdie support shown in Figs. 5, 6 and 'I which results in the fosetall being onl the top is readily'and inexpensively made, and in which the movement oi the dies together to iiattenv the terminal end-is underthe forces created by a detonated explosive charge so that the tubing and the wire end are intimately bonded or crushed together under comparatively high forces which may be up to or even over 50,000 pounds per square inch. These forces literally ow the inner surface of the tubing and the outer surface of the wire together to thereby provide substantially perfect electrical conductivity. The terminal or connector can be made in substantially any size desired and from any of the materials heretofore indicated. The terminal can not fail in any heavy overload, and is less expensive and more easily and quickly applied than the standard cast or pressed terminal, particularly in the larger sizes. There is no heating or soldering required, and the bare wires themselves extend to the end of the terminal so that a particularly good,me chanical and electrical connection is made between the wire and the tubing.

My improved apparatus operating from the po'wer of a blank cartridge can be made relatively light and inexpensive and yet the apparatus will function over long periods of time substantially without maintenance orv repair, and by substituting die sizes and'shapes as described I can readily adapt my apparatus. to compress terminals of a plurality of sizes. The operation of my improved press is readily mastered bythe ordinary unskilled workman and operates relatively rapidly and without noise to achieve the' pressing and flattening of the tubing end to form a terminal or connector. Moreover, since the terminal itself is formed from an ordinary piece of tubing, the expense thereof is kept at a minimum, and supply and stocking of various sizes is a simple matter.

While in accordance with the patent statutes I have illustrated and described specically one particular embodiment of my invention, it should be understood that my invention is not limited thereto or thereby but is defined in the appended claims. i Y

I claim:

1. A terminal for a wire end comprising a length of metal tubing receiving the bare end of the wire snugly within its b'ore, the outermost end of the tubing being substantially flush with the outermosty end of the wire, said 'tubing and wire therein being flattened andY compressed firmly together over at least one end of the tubing, and the flattened V end of the tubing and wire having a hole punched therethrough.

2. A terminal or connector for the bare end of an insulated wire and comprising a short length. of metal tubing receiving the bare end of the wire snugly within its bore, the outermost end of the tubing being substantially iiush with the outermost `end of the wire, said tubing and wire therein being flattened and compressed iirmly together over at least one end of the tubing, from one side thereof to offset such portion from the unilattened wall, the side of the tubing opposite said portion being substantiallyfin line with the unilattened wall of the tubing, the flattened end of the tubing and wire having a hole punched therethrough, and the innermost end oi the metal tubing being belled to receive the end of the insulation on the wire in substantially sealing relation therewith.

3. A terminal adapted to connect a wire of one metal to a member of another metal and comprising a length of metaltubing receiving the bare end of the wire snugly within its bore, .said tubing being of substantially thesame material as the wire. amouter tubing of a diii'erent metal which is substantially the same as the metal of the member to be connected. said outer tubing closely surrounding the inner tubing, the outermost ends of the tubings being substantially flush 5 with the outermost end of the wire, said tubings and wire therein being attened and compressed firmly together over one end of the tubings, the iiattened end of the'tublngs and wire having a hole punched therethrough.

4'. A terminal for a wire end comprising a short length of metal tubing receiving the bare end of the wire snugly within its bore, the outermost end of the tubing being substantially flush with the outermost end of the wire, said tubing and Wire therein being iiattened and compressed iir'mly together over at least one end of the tubing, the flattened end of the tubing and wire ,n having a hole punched therethrough, the sides of the Viiattened end being inclined slightly outwardly relative to the bottom of the flattened end, and the bottom of the ilattened end of the tubing Vbeing substantially in line with the uniiattened wall ofthe tubing and the top of the flattenedend being offset from the untlattened Wall of the tubing. 5. A terminal forl a wire end comprising a length of metal tubing receiving the bare end of the wire snugly within its bore, said tubing and wire therein being flattened and compressedf the iiattened end being inclined slightly 'outwardly relative to the bottom of the flattened end, and the bottom of the flattened end of the tubing being substantially in line with the unfiattenedrwall of the tubing and the top of the iiattene end being onset from the unflattened wall of the tubing.

6. A terminal for a wire end comprising a length of metal tubing receiving the bare end of the wire snugly within its bore, said tubing and Wire therein bein flattened and compressed firmly together ov r at least one end of the tubing, the flattened end of the tubing and wire having a. hole punched therethrough, and the bottom of the attened end of the tubing being substantially in line with the unflattened wall of the tubing and the top of the flattened end being offset fromthe uniiattened wall of the tubing.

'7. A terminal for a wire end comprising a length of metal tubing receiving the bare end of the wire snugly within its bore, said tubing and wire therein being flattened and compressed ilrmly together over at least one` end of the tubing, the flattened end of the tubing and wire having a hole punched therethrough; and the sides ,of the flattened end being inclined slightly outwardly relative to the bottom of the fiattened end.

il. That method of making a terminal or connector on the endy of a wie which comprises providing a length of metal tubing having an inside diameter adapted to closely receive and surround the end of the wire, placing the end of the wire in 'the tubing so that the wire extends substantially throughthe tubing, and simultaneously flattening the outermost end of the tubing and the wire ,therein from one side thereof to4 offset such Iportion from the unflattened portion while maln- 70 taining the side opposite the flattened portion ubstantially in line with the unattened porion.

9. That method of connecting a member of one metal to the end of a wire of a dierent metal 76 whichincludes the steps of4 providingca short length ommetainc tubing having an inside surface of substantially the same metal as the WireA and adapted to closely receive and 'surround the bare end of the wire and anV outside surface of substantially the same metal as the member,

placing the end of the'. Wire in the tubing S0 that the wire extends substantially through the tub- Y ing, ilattening the outermost end o! the tubing i and the wire therein by' means o! the detonation of anexplosive charge, punching a hole vthrough the iiattened end by the power of the detonation .of the same explosive charge, and joining the outside surface of the terminal to the member to be connected.

10. That method of making a terminal or connector on the" end o! a wire which comprises providing a length of metal tubing having an inside diameter adapted to closely receive and surround the end of the wire, placing the end oi the wire in the tubing, attening the outermostend of the tubing by means of the detonation Voi an explo.

` nector on the bare endof awire which comprises providing a short length of metal tubing having` l0 an inside diameter adapted to closely receive and punchinga hole through the end-.of the tubing `and wire by the'power of the detonation of the same' explosive charge. Y Y

12. That method ot making aterminal ot consurround the bare end of the wire, placing the end of the'wire in the tubingso. that thewire extends. substantially through the tubing, 'ii'attening the outermost end ofthe tubing and the sive charge. and punching .a hole through the ilattened end by the power of the detonation of the saine explosive charge.

11. That methode! making a terminal or connectorontheendotawirewhichcomprlsesproviding a length oi metal tubing having an inside theendotthewire,placingtheendofthewire intlietublngsothatthewireextendssulistantially through the tubing, attening the outerdiameter adapted to closeiyreceive and surround wirel therein lay-means o! the detonation of an detonation of the-same explosive charge to punch a hole throughthe ilattened end after it has substantially completely'iiattened.

5A most end ofthe tubing and the wire therein by v means o! the detonation of an explosive charg,` and simultaneously with the iattening operation -explosive charge,-and utilizing the power of the 13'. matmetnod of making a' tennmai or'con'- nector on the end oi' a wire whichA comprises providing a length of metal tubing adapted to receive awlreendinitsbore,placingtheendofthe wireil'lthetllbingsothtth'ewlreextendsslIb-- stantially through the tubing and simultaneously the wire therein while positively coniining the l sides o! thetubing so that the tubing inthe ilattenedportionis ot atrapegoidalcrosssectionn 30 ROBERT on.

the outermost end of thetubing and y